Sylvania



UNiTnn STATES JAMES J. FRONHEISER AND CHARLES S. PRICE, O F

PATENT OF IC JonNs'rowN, runs- I SYLVANILA'.

MANU'FACTURE'OF COKE.-

S PEGIFIQATION forming part ofLetters Patent No. 486,100, dated ovember Application filed December 17 1891. Serial F0. 415,351. (No specimens.)

and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

In the manufacture of coke from soft coal in retort ovens, particularly in those constructed so as to save the by-products formed in the coking operation,the coke has the disadvantageof being more porous, softer, with moreeasily crushed cell-walls than when the same coal is coked in the ordinary beehiveoven. This softer coke has the disadvantage of. being easily acted on or dissolved, as it were, in thenpper part of the blast-furnace and cupola by the carbonic-acid gas generated in the lower zones of the apparatus, which, taking up carbon from the coke, for-ms oarbonic-oxide gas thus:

Owing to the property of the carbonic acid of being readily converted into carbonic oxide in this manner at the expense of the solid carbon of the coke it will require a greater quantity of such soft coke to furnish the same numbcrof heat-units in the hearth of the blastcryolite, &c., or other solid matter suitable for a flux in the blast-furnace orcupo1a-will all answer this. purpose. A suitable solid hardening substanceis onewhich will satisfy part of the sulphur contained in the coal, will thereby wasting 'unite with the free silica formiuga silicate of thebuse, and by mechanical mixture will till up the pores of the coke, thereby rendering it more dense. "The advantage gained by the use of lime or other basic material is that the excessive quantity used will serve the purpose of uniting with the free silica in the blast-furnace or cupola charge to form a proper flux,

and as substances containing any free silica will not do this it is not desirable to use them.

Among the reasons for preferring, caustic lime is its cheapness as compared-with that of other suitable materials and also its'use- [illness in the blast-furnace or cupolaas a base to unite with the silica of the charge for the formation of a slag. While limestone or .carbonateof lime in its different forms of combination may be used, they have the disad vantage that their carbonic acid eliminated in the process of coking acts on the carbon ofthe coal in the formation of carbonic oxide,v part of the carbon of the coal.

In our practice we grind the coal by any of the well-known methods which will reduce it to a coarse powder. We then add to this mass a flnxing material, preferably caustic lime, either in a dry state or in a wetted'and pasty condition, mixing the same thoroughly, after which it is charged into the coke-oven, as in the ordinary practice. There is an advantage in introducing into the cnpola. or furnace, is

combination with the coke, a fluxing material such as is needed in the metallurgical operation carried on therein, and this is effected in our practice, as the caustic lime or otherfiux ing material used is mechanically combined with the coke, filling up its cell-walls.

find that about 'p' by ght, of-

caustic lime mixed with the fine coal gives the best results.

lime can be added to coals containing more than five to seven per cent. of ash.

We are aware that inthe manufacture or illuminating and heating gas, coal has been pulverized and mixed with lime to unite with the sulphur of the coal and with-tar, naphtha,

However, a larger quantity of r and other heavy hydrocarbons in order to in: crease its illuminating properties, in all of which coke is a by-product, undthis we do not claim.

Having thus fully described-our invention,

a aeegoo 5 ing therewith a suitable hardening substance,

charging the same into ovens, and beating them, substantially as described.

2. As a new article of manufacture, coke hardened by combining with it caustic lime to or other suitable solid hardening substance in the process of its manufacture in such a manner that the proportion of its cell-space to its cell-walls is diminished, givingto it greater density and firmness, substantially as described.

In testimony whereof we affix our signat arcs in presence of two witneses.

JAMES J. FRONHEISER. CHARLES S. PRICE. \Vitnesses:

Ii. ii. WEAVER, H. L. BOYLE. 

